Road grader



1951 J. G. MACDONALD 2,577,134G

ROAD GRADER- Filed July 8, 1948 4 Sheets-Sheet l [rm/anion John 3 Haco/ona/a/ Dec. 4, 1951 .1. G. MACDONALD ROAD GRADER Filed July 8, 1948 4 Sheets-Sheet 2 4 F EM W W i A J w Dec- 4, 1951 J. G. MACDONALD 2,577,349

I ROAD GRADES Filed July s, 1948 4 Sheets-Sheet 5 Dec. 4, 1951 J. 5. MACDONALD 2,577,34@

ROAD GRADER Filed July 8, 1948 4 Sheets-Sheet 4 Patented Dec. 4, 1 951 ROAD GRADER John G. Macdonald, Goderich, Ontario, Canada, assignor to The Dominion Road Machinery (30., Limited, Goderich, Ontario, Canada Application July 8, 1948, Serial No. 37,615

8 Claims.

This invention relates to improvements in road graders and the principal object of the invention is to provide an extremely sturdy and simple grader construction in which the scraper blade can be easily and accurately controlled in elevation, transverse inclination and position beneath the machine, and can be readily operated to swing from a position under the machine to a bank cutting position of any desired steepness at one side of the machine.

A further important object is to provide a fully adjustable scraper blade while eliminating the requirements for the conventional complex rotating assembly on which the blade controlling power mechanism is normally carried.

A still further object is to provide a grader which may be readily serviced and in which many of theassemblies are interchangeable and may be readily removed and replaced. I

'A further important object is to provide a grader wherein no separate power mechanism is required to operate the scraper blade to bankcutting position.

A further important object is to transmit lateral strains on the scraper blade directly to the machine frame eliminating destructive side thrusts on the blade-operating mechanism.

A still further object is to provide a grader which will be readily controlled from a single control position requiring the minimum of controls.

The principal feature of the invention consists in pivotally supporting a pair of transversely spaced carriages either side of the machine frame to swing in opposite directions in positions above and below theframe, providing means for locking the carriage against movement, universally supporting a pair of hydraulic cylinders on the carriages with their piston rods secured to and supporting the rear of-a scraper carrying drawbar frame swivelly supported at its forward end to the machine frame, and providing means for side shifting the drawbar frame, thecarriages being operable upon release of their locking means to swing in opposite directions under movement of the pistons in the cylinders to change the planes of support of the cylinders to permit the scraper tobe swung to a. high bank cutting position.

A further important feature consists in enabling the transverse shifting of the drawbar frame. 1 v

A still further important feature consists in forming the cylinder-carrying carriages of identical castings to permit their ready interchangement.

A still further featureconsists in forming the pivotal carriages with segment-shaped exten-r sions terminating in stop pr'ojectionsland pro viding stops on the supporting frame'co-operating with the stop projections to li nit movement of the carriages from a horizontal position to positions directly above or directly below their pivots.

A still further feature consists in mounting the hydraulic supply pipes in a concealed protected position within the grader frame to preclude damage thereto.

Referring to the accompanying drawings, Figure 1 is a side elevational view of a grader embodying my invention.

Figure 2 is a plan view of the grader of Figure 1.

Figure 3 is an enlarged perspective view of the front portion of the grader illustrating my novel scraper blade controlling mechanism.

Figure 4 is a front elevational view of the blade controlling cylinder carriages illustrating the position to which the carriages are swung for operating the scraper blade to bank-sloping position. 7

Figure 5 is a diagrammatic view of the scraper blade and its controlling mechanism showing the blade located in normal road-engaging relation.

Figure 6 is a view similar to Figure 5 showing the scraper blade side-shifted to the left.

Figure '7 is a view similar to Figure 5 but showing the scraper blade side-shifted to the right.

Figure 8 is a diagrammatic view showing the scraper blade elevated to a bank-sloping position and illustrating the position to which the carriages are swung to change the planes of support of the blade-controlling cylinders to permit the oblique elevation of the blade.

Figure 9 is a sectional detail taken on the line 9-9 of Figure 5 and showing the slide operating on the drawbar frame to permit side shifting of the scraper blade.

Referring to the drawings, it will be seen that the grader frame generally designated at I is formed at the forward end by two abutting channel beams 2, Figures 3 and 1, which extend angularly upwardly towards the rear of the grader and adjacent the rear they divide to form two spaced frame bars 3 extending horizontally below the angled forward part of the frame to support the engine 4 and cab 5.

The noseofthe grader frame t-extends downwardly and is supported by the wheels 1, while the rear of the grader frame is supported by the two sets of wheels 8 and 9.

Arranged at the nose of the frame and covering the open end of the hollow beams formed by the two channels 2 is a nose plate is which is formed with an opening I! therethrough, the purpose of which will hereinafter be explained. Swivelled to the nose of the grader frame is adrawbar l 2, the swivel connection being formed by the interlocking engagement of the eye-bolt 13 carried by the drawbar and the U-shaped pin [4 secured in the nose of the frame.

vPivotally supported to the underside of the drawbar I2 is an internally toothed ring [5 to which the scraper blade or mould board [6 is secured. Mounted on the drawbar adjacent the forward end is a suitable hydraulic motor H, the shaft of which drives, through the gear box 18, the scraper blade-carrying ring l5. transverse angle of the scraper blade can be controlled at will through the operation of the hydraulic motor ll.

Secured to the end' of the drawbar and extending transversely thereof is an angle bar l9 and mounted on and secured to the rearward face of the upright leg of this angle bar I9 is asideshiftin cylinder 28 which extends longitudinally of the angle bar.

Arranged between the cylinder and the angle bar is a guideway 21 extending longitudinally of the bar, Figure 9, and mounted on this guideway and slideably engaging therewith is a slide 22 which is connected to the end of the piston rod 23 of the cylinder 29 by means of the pin 24 secured in lugs 25 carried by the slide. Movement of the piston rod in its cylinder thus accomplishes relative movement of the slide and the drawbar frame as formed by the angle bar [9 and drawbar 12, the slide moving freely on the guideway 2i.

Secured to the channel beams 2 immediately above the end of the drawbar is a transverse frame or saddle 23. Pivoted at each end of the saddle 2% are interchangeable frames or carriages 2'! which may be formed as simple castings.

Each of the castings 21 comprises a body portion 23 and spaced projections 29 and 30 which form a yoke to receive the end of the saddle or frame 26 and through which the pivot pin 3| extends. The forward projection 30 is considerably larger than the projection 29 and is sectorshaped defining a quadrant of a circle.

Extending beyond the curved periphery of the projection at each end of the sector are adjustable stop projections 32, while extending through the sector opposite the inner edges of the stop projections 32 are bushings 33 which receive the hardened pins 34 carried at the end of the operating rods 35 and extending through the saddle 25. Thus each of the carriages 21 is freely swingable about its pivot 3! with the stop pins 35 withdrawn from the bushings 33, and these carriages may be swung through 90 as permitted by the stop projections 32 which are ranged to Engage with the stop pins 36 carried by the sad- In the normal operation of the scraper blade as shown in Figure 3, the carriages 21 are swung until the body portions 28 are in alignment with the saddle, at which position one of the stops 32 will be against its corresponding stop pin 35, and the hardened locking pin 34 will engage in the throughthe control levers 31 arranged in the cab of the grader. The rearward movement of these rods to withdraw the locking pins 34 is against the restraint of the springs 38 which engage the pins and the guide lugs 39.

i 'Universally supported on the body portions 28 of the carriage castings are hydraulic cylinders 40, the piston rods M of which are connected to the angle bar IQ of the drawbar frame by means of the pivot pins 42 secured in the brackets 43.

Extending downwardly from the right-hand end of the saddle 26 and pivotally connected thereto is a telescopic hanger 44, the lower end of which is pivoted to the bracket 45 carried on the slide 22. This hanger 44 thus forms a rigid extensible connection between the grader and the drawbar frames one form being shown in Figures 1, 2, 3 and 9 and a simplified form in the diagrammatic views Figures 5 to 8.

The necessary hydraulic pressure for the hydraulic motor l! and any other hydraulic equipment required at the front of the grader for turning the wheels or other attachments is supplied through suitable tubes 46, Figures 1 and '3, which extend through the hollow forward portion of the frame as defined by the channel beams 2. These tubes are formed with downturned forward ends 31 which are arranged to project through an opening 48 in the underside of the frame and are fitted for connection with the hydraulic flexible hose lines leading to the hydraulic equipment to be operated.

To permit the insertion of these tubes into the channels as described, the nose plate is formed with an opening II and during assembly the tubes or pipes 46 are inserted through this opening and are then lowered until their ends extend through the opening 48. Before their assembly the tubes are preferably coated with a suitable tar substance to surround the tubes, forming a protection therefor and securely holding same in place against dislodgement under the heavy vibration set up during the work of the grader.

bushing adjacent the stop engaged by the stop 7 Since the carriages are identical castings they must be reversed when fitted to opposite ends of the saddle. It will therefore be seen from Figure B that when the hardened pin 34 is withdrawn through operation of the rod 35 to release the right-hand carriage its stop projections are so arranged that the carriage can only move to swing its body portion upwardly above the saddle and grader frame.

are so arranged that it can only swing in a direction to move its body portion 28 downwardly of the saddle and grader frame.

As shown in Figure l, the rods 35 are opera ed These tubes are arranged to project from the end of the rearward portion of the frame as formed by the channel beams 2 and are connected to a valve bank 50 located in the cab of the grader. This valve bank may be of any suitable type to permit the ready control of the fluid flow to the hydraulic equipment, the hydraulic pressure being supplied by a pump on'the grader engine 4. 7

During normal grader operation when the scraper blade or mould board is to-be used on a road or similar surface the carriages 2'! are swung to their normal position as shown in Figure 3 or Figures 5 to '7. In this position the planes of support of the two cylinders 40 are the same and the rearward end of the drawbar frame is supported by the piston rods 4! and the telescopic hanger 44. t

This hanger 44 may if desired be in the form of anhydraulic ram, orlas shown may simply comprise a rod 5| operating in a sleeve 52, the

rod being held in adjusted positions in the sleeveby a pin 53 extending through the sleeve and rod. With the piston rod '23 of the side-shifting cylinder 20 in an intermediate position the cylinders 40 will be substantially vertical, toeing in slightly. This is the position assumed under nor-- mal grading conditions with thedrawbar frame substantially in line with the grader frame.

Theangle of. the scraper blade can of course bdreadily controlled through operation of the hydraulic motor I! which is preferably reversible to facilitate control.

When it is desired to project the scraper blade to the right as viewed from the rear, fluid pressure is delivered to the side-shifting .cylinder 20 to force its piston rod outwardly.

Since the position of the slide 22 is determined by the hanger 44 secured to the slide and grader frame, the outward movement of the piston effects the lateral movement of the whole drawbar frame, forcing same to the right as seen in Figure 7.

As the blade moves to the right the cylinders 40 assume the position as shown in Figure 7. Conversely when side-shifting to the left as viewed from the rear is desired, the piston rod 23' of the cylinder 20 is retracted and again since the position of the slide is controlled by the hanger 44 the whole drawbar frame shifts to the left and the cylinders 40 assume the position of Figure 6.

In any of the positions of the scraper blade as shown in Figures 5, 6 and 7 the elevation of the blade is controlled by the cylinders 40.

When it is desired to swing the scraper blade to a bank-sloping position the drawbar frame and 'of this carriage is accomplished by retracting the piston rod 4| of its cylinder 40. Thecarriage then moves to the position shown in Figure 8, and upon reaching this position, as determined by the stoppin 36, the co-operating lock pin 34 snaps into the adjacent bushing 33 under action of the spring 38.

The carriage is thus locked in position against movement with its body portion rotated through 90 to a position directly below the end of the saddle to support the cylinder 40 at a point below the saddle and inwardly of its normal point of support. 1

Similarly upon release of the right-hand carriage, as viewed from the rear, by its locking pin 34 the right-hand carriage is free to swing but its movement about its pivot pin must be in a direction to swing its body portion 28 upwardly above the saddle, since the lower stop 32 bars clockwise rotation of the carriage.

The upward movement of the carriage body portion is effected by means of the cylinder 40 carried thereby through extending 'its piston rod 4!. Thus upon extension of the piston rod 4| under fluid pressure the right-hand carriage 21 swings upwardly until the upper stop 32 engages the stop pin 36 and the lock pin 31 snaps into the adjacent bushing under action of the cylinders 40 can be operated to swing the scraper blade to a high bank-sloping position.

The initial side-shifting of the drawbar frame before rotating the carriages is required to move the connections between the cylinder piston rods and the drawbar frames from directly beneath the pivots of the cylinders so that they will provide the desired action for effecting the carriage movements.

Figure 4 shows the position of thecarriages for actuating the scraper blade to bank-sloping position as viewed from the front. In this case the scraper blade is shown in an intermediate and in maximum sloped positions for cutting intermediate or vertical banks. The figure also indicates the movement of the drawbar as permitted by its swivel connection to the front of the grader frame.

t is important to note that the construction of the carriages, which may be simple castings, provides a relatively inexpensive construction which permits the full control of the scraper blade from grading to bank-sloping positions. Previously such blade control has necessitated the use of complicated and expensive rotating saddles which required additional motive power to effect their rotation and which greatly increased the cost and upkeep of the grader.

With the carriage arrangement described and shown the blade-controlling and operating cylinders also effect the operation of the simple carriages, reducing the number of the hydraulic cylinders to a minimum. I

In addition, with my construction it is important to note that the side-shifting cylinder which is mounted on the drawbar frame always acts to employ the full fluid pressure acting on its piston rod to effect relative movement of the slide and drawbar frame independent of the position of the drawbar, that is, there is no component of force set up by extension or retraction of the cylinder piston which does not operate to effect positive movement of the slide and drawbar.

During bank-sloping operations the scraper blade and drawbar frame are subjected to large side or lateral strains and this strain is transmitted directly to the grader frame through the hanger 4 3. Similarly the strain resulting from the side-shifting of the drawbar is transmitted directly to the grader frame and the pivotal carriages are completely relieved of these heavy streses, enabling their construction to be'relatively light.

The fact that the number of moving parts has been reduced to a minimum and that the moving control frames or carriages 2'! are inexpensive to construct and are interchangeable, the initial cost of the grader is greatly decreased over the previous complicated structures, and further, the grader may be readily and inexpensively serviced and maintained, with the carriage and associated cylinder being readily removed and replaced as a unit.

It will be understood that where the limits of movement of thescraper blade during side shiftil'lg are desired to be changed the telescopic hanger can be adjusted upon removal of the pin 53 and when adjusted to give the desired stroke of the scraper blade, can be relocked by the pin.

The grader may of course carry other additional equipment and various minor modifications may be made without departing from the scope of my invention.

What I claim as my invention is; Y, 7

1. In a road grader, the combination with a support frame, a drawbar swivelled thereto adjacent its forward end and a scraper blade rotatably supported from said drawbar, of a slide carried by and transversely slidable of said drawbar adjacent the rear thereof, hanger means pivotally connected between said support frame and said slide affording a rigid strut permitting swivelling of the rear of said drawbar relative said frame while maintaining the spacing of said frame and drawbar, means to effect the relative movement of said slide and drawbar to side shift said scraper blade, transversely spaced support means carried by said support frame and pivoted to swing about axes arranged on opposite sides of said support frame and outwardly of said support frame to adjusted positions relative thereto, releasable lock means for holding said support means in adjusted position, and hydraulic cylinder means connected between said drawbar and said support means transferring reactive thrusts from said scraper blade and effecting the movement of said support means when released and for moving the scraper blade from road grading to bank-sloping position when said support means are locked in adjusted position.

2. In a road grader the combination with a support frame a drawbar swivelled thereto adjacent its forward end and a scraper blade rotatably supported from said drawbar, of a slide carried by and transversely slidable of said drawbar, hanger means connected between said support frame and said slide and forming a rigid strut permitting swivelling of said drawbar and slide while maintaining the spacing of said frame and drawbar, means to effect the relative movement of said slide and drawbar to side shift said scraper blade, adjustable support means carried by said support frame pivoted to swing on fixed axes on opposite sides and outwardly of said support frame, cylinders carried by said adjustable support means in transversely spaced relation relative said support frame, and pistons operating in said cylinders and having rod extensions connected with said drawbar to control the elevation of the scraper blade during road grading and to effect the movement of the scraper blade from road grading to bank-sloping position upon adjustment of said adjustable support means.

3. In a road grader, the combination witha support frame, a drawbar swivelled thereto adjacent its forward end, a scraper blade rotatably supported from said drawbar, and means to effect the rotation of said scraper blade, of a guideway carried by and extending transversely of said drawbar, a slide operating on said guideway, hanger means connected between said support frame and said slide, means to effect the relative movement of said slide and drawbar to side shift said scraper blade, a saddle carried by said support frame and extending transversely thereof, support carriages pivoted adjacent the ends of said saddle on opposite sides of said support frame and swingable inopposite directions relative to said support frame, releasable lock means for holding said carriages in adjusted position, cylinders universally supported on said carriages, pistons operating in said cylinders and connected to support said drawbar, said pistons, upon movement, swinging said carriages, when released, to adjusted positions to vertically shift the points of support of said cylinders and being operable with said scraper blade side-shifted and said carr iages locked inadjusted position with the points of support of said cylinders vertically shifted to swing said scraper blade from road-grading to bank-sloping position. a d

4. A device as claimed in claim 3 in which said carriages are interchangeable castings.

5, A device as claimed in claim 3 in which each of said carriages is formed with a sector shaped extension having a center coincident with its pivot and having stop projections formed adjacent the ends of the arcuate perimeter thereof, said saddle having stop means to engage said stop projections to limit the swinging movement of said carriage to the arc of said sector-shaped extension. 7 7

6. A device as claimed in claim 3 in which each of said carriages is formed with a sectorshaped extension having arcuately spaced openings therethrough, and said releasable lock means comprises a pin associated with each carriage and extending through said saddle to selectively engage in said arcuately spaced openings.

'7. A device as claimed in claim 3 in which each of said carriages is formed with a sectorshaped extension having a center coincident with its pivot and having adjustable stop means formed adjacent the ends of the arcuate perimeter thereof, said saddle having stops to engage said adjustable stop means to accurately control the limits of the swinging movement of said carriage and to facilitate the operation of said releasable lock means.

8. In a road grader, the combination with a support frame, a drawbar swivelled thereto adjacent its forward end and a scraper blade rotatably supported from said drawbar, of a pair of carriages mounted on said supporting frame on opposite sides thereof for pivotal movement relative thereto, hydraulic cylinder means universally supported on said carriages and connected with said drawbar, releasable locking means for holding said carriages'in one of two positions, one with said cylinder means supported in horizontal alignment with said support frame and the other with the points of support of said cylinder means in vertical alignment with the pivots of said carriages, .a hanger pivotally suspended from said support frame adjacent the rear'of said drawbar, and side-shifting cylinder means connected between said drawbar and said hanger to side-shiftsaid drawbar with said cylinder means supported in horizontal alignment with said sup port frame and to permit the swinging of said scraper blade to high angle bank-sloping position with said carriages swung to bring the supports of said cylinder means into vertical alignment with the pivots of said carriages, said carriages being swung between said two-positions upon release of said locking means by said cylinder means.

JOHN G. MACDONALD.

REFERENCES 'orrnn The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,247,007 Arndt June 24, 1941 

